The drug, called Molly, is usually a pure form of MDMA which is the main ingredient in Ecstasy. But officials warn that it can also refer to other synthetic stimulants and can be cut with additional dangerous substances.

There have been 11 calls to the Hennepin Regional Poison Center about Molly this year, Dr. Ben Orozco, the center's associate medical director, told MinnPost.

"Prior to that, the term would come up a couple times a year," he said. "It is definitely an emerging problem..."

The synthetic drug, popular at clubs and music festivals, boosts three chemicals in the brain: serotonin, dopamine and norepinephrine, he said. Someone who takes it will feel happy, experience mild hallucinations and feel like touching people around him or her.

Although it's considered rare, death from pure MDMA can happen several ways, Cowan said. It can cause blood vessels in the heart and brain to constrict and result in a stroke or heart attack. The stimulant, which raises the user's blood pressure and heart rate, can also cause the body to get severely overheated, causing fatal brain damage. Finally, it can cause blood sodium to drop, prompting the brain to swell and resulting in a fatal seizure. Dehydration and over-hydration are also common.